CN114483208A

CN114483208A - Seal assembly for a gas turbine engine having a leaf seal

Info

Publication number: CN114483208A
Application number: CN202110988128.3A
Authority: CN
Inventors: M·T·拉万斯基; D·G·塞尼尔
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 2020-10-26
Filing date: 2021-08-26
Publication date: 2022-05-13
Also published as: US20220127967A1; US11761342B2

Abstract

The present invention relates to a seal assembly for a gas turbine engine having a leaf seal. The seal assembly includes first and second gas turbine walls defining a passage therebetween. In addition, the second gas turbine wall also defines a passage extending therethrough. Further, the seal assembly includes a leaf seal positioned partially within the passage, and a seal retainer coupled to the second gas turbine wall. Further, the seal assembly includes a spring compressed between the seal retainer and the leaf seal such that the leaf seal is in sealing engagement with the first gas turbine wall. Further, the seal assembly includes a pin extending through a passage defined by the second gas turbine wall to couple the seal retainer and the leaf seal such that the pin is not thermally constrained by the second wall during operation of the gas turbine engine.

Description

Seal assembly for a gas turbine engine having a leaf seal

Federally sponsored research

The invention was accomplished with government support. The government may have certain rights in the invention.

Technical Field

The present disclosure relates generally to seal assemblies for gas turbine engines and, more particularly, to seal assemblies for gas turbine engines having leaf seals.

Background

Gas turbine engines generally include a compressor section, a combustion section, and a turbine section. More specifically, the compressor section gradually increases the pressure of the air entering the gas turbine engine and supplies the compressed air to the combustion section. The compressed air and fuel are mixed in the combustion section and combusted within the combustion chamber to generate high pressure and temperature combustion gases. The combustion gases flow through a hot gas path defined by the turbine section before exiting the engine. In this regard, the turbine section converts energy from the combustion gases into rotational energy. The rotational energy, in turn, is used to rotate one or more shafts that drive a compressor section and/or a fan assembly of the gas turbine engine.

The turbine section includes various stationary components (e.g., stator vanes, turbine shrouds, shroud supports, etc.) that partially define a hot gas path through the turbine section. While the components defining the hot gas path can withstand prolonged exposure to combustion gases, components positioned outside of the hot gas path (e.g., the turbine casing) typically have less favorable thermal characteristics. In this regard, metal leaf seals (leaf seals) are positioned between adjacent stationary components to minimize leakage of combustion gases from the hot gas path.

In recent years, the use of composite materials, such as Ceramic Matrix Composite (CMC) materials, in gas turbine engines has increased dramatically. For example, stator vanes are typically formed from CMC materials to reduce the weight of the engine and/or increase the operating temperature range of the engine. However, the use of composite materials in gas turbine engines presents various challenges. For example, coupling metal leaf seals to composite gas turbine components is difficult.

Accordingly, an improved seal assembly for a gas turbine engine would be welcomed in the technology.

Disclosure of Invention

Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.

In one aspect, the present subject matter relates to a seal assembly for a gas turbine engine. The seal assembly includes a first gas turbine wall and a second gas turbine wall spaced from the first gas turbine wall, wherein the first gas turbine wall and the second gas turbine wall define a passage therebetween. In addition, the second gas turbine wall also defines a passage extending therethrough. Further, the seal assembly includes a leaf seal positioned partially within the passage, and a seal retainer coupled to the second gas turbine wall. Further, the seal assembly includes a spring compressed between the seal retainer and the leaf seal such that the leaf seal is in sealing engagement with the first gas turbine wall. Further, the seal assembly includes a pin extending through a passage defined by the second gas turbine wall to couple the seal retainer and the leaf seal such that the pin is not thermally constrained by the second wall during operation of the gas turbine engine.

In another aspect, the present subject matter relates to a stator vane for a gas turbine engine defining an axial centerline. The stator vane includes an inner band, an outer band spaced from the inner band in a radial direction extending orthogonally outward from an axial centerline, and an airfoil extending between the inner band and the outer band. Further, the stator vane includes a first wall extending outwardly in a radial direction from at least one of the inner band or the outer band, and a second wall extending outwardly in a radial direction from at least one of the inner band or the outer band. The second wall is spaced from the first wall along the axial centerline such that the first wall and the second wall define a channel therebetween. In addition, the second wall also defines a passageway extending therethrough. Further, the seal assembly includes a leaf seal positioned partially within the channel, and a seal retainer coupled to the second wall. Further, the seal assembly includes a spring compressed between the seal retainer and the leaf seal such that the leaf seal is in sealing engagement with the first wall. Further, the seal assembly includes a pin extending through a passage defined by the second wall to couple the seal retainer and the leaf seal such that the pin is not thermally constrained by the second wall during operation of the gas turbine engine.

These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

Technical solution 1. a seal assembly for a gas turbine engine, the seal assembly comprising:

a first gas turbine wall;

a second gas turbine wall spaced apart from the first gas turbine wall, the first and second gas turbine walls defining a channel therebetween, the second gas turbine wall further defining a passage extending through the second gas turbine wall;

a leaf seal positioned partially within the channel;

a seal retainer coupled to the second gas turbine wall;

a spring compressed between the seal retainer and the leaf seal such that the leaf seal is in sealing engagement with the first gas turbine wall; and

a pin extending through the passage defined by the second gas turbine wall to couple the seal retainer and the leaf seal such that the pin is not thermally constrained by the second wall during operation of the gas turbine engine.

Solution 2. the seal assembly of any preceding solution, wherein the pin comprises a pin shaft having a pin shaft diameter that is less than a passage diameter of the passage.

The seal assembly of any preceding claim, wherein the second gas turbine wall includes a passage surface defining the passage, the pin extending through the passage such that the pin is spaced apart from the passage surface.

The seal assembly of any preceding claim, wherein the second gas turbine wall includes a first surface partially defining the passage, a second surface spaced from the first surface, and a third surface extending between the first surface and the second surface, the passage extending from the first surface to the second surface.

Claim 5. the seal assembly of any preceding claim, wherein the passageway comprises a recess.

Claim 6. the seal assembly of any preceding claim, wherein the third surface of the second gas turbine wall defines an opening of the recess.

Claim 7. the seal assembly of any preceding claim, wherein the notch extends from the opening into the second gas turbine wall in a circumferential direction that extends concentrically about an axial centerline of the gas turbine engine.

The seal assembly of any preceding claim, wherein the seal retainer comprises a body and a hook coupled to the body, the body being in contact with the second surface, at least a portion of the hook being in contact with the first surface.

The seal assembly of any preceding claim, wherein the second gas turbine wall further comprises a fourth surface extending between the first and second surfaces, the fourth surface being orthogonal to the third surface, the hook extending from the body around the fourth surface to contact the first surface.

The seal assembly of any preceding claim, wherein the seal retainer includes a support arm configured to prevent rotation of the seal retainer relative to the second gas turbine wall.

Solution 11. the seal assembly of any preceding solution, wherein the first and second gas turbine walls are formed of a composite material, and the leaf seal, the seal retainer, the spring, and the pin are formed of a metallic material.

Technical solution 12. a stator vane for a gas turbine engine defining an axial centerline, the stator vane comprising:

an inner band;

an outer band spaced from the inner band in a radial direction extending orthogonally outward from the axial centerline;

an airfoil extending between the inner and outer bands;

a first wall extending outwardly from at least one of the inner or outer bands in the radial direction;

a second wall extending outwardly from the at least one of the inner or outer bands in the radial direction, the second wall being spaced apart from the first wall along the axial centerline, the first and second walls defining a channel therebetween, the second wall further defining a passageway extending therethrough; and

a seal assembly, comprising:

a leaf seal positioned partially within the channel;

a seal retainer coupled to the second wall;

a spring compressed between the seal retainer and the leaf seal such that the leaf seal is in sealing engagement with the first wall; and

a pin extending through the passage defined by the second wall to couple the seal retainer and the leaf seal such that the pin is not thermally constrained by the second wall during operation of the gas turbine engine.

The stator vane of any preceding claim wherein the seal assembly sealingly engages the outer band.

The stator vane of any preceding claim, wherein the seal retainer comprises a support arm configured to prevent rotation of the seal retainer relative to the second wall.

The stator vane of any preceding claim wherein the seal assembly sealingly engages the inner band.

The stator vane of any preceding claim, wherein the at least one of the inner band or the outer band extends along the axial centerline from a forward end to a rearward end, the seal assembly sealingly engaging the at least one of the inner band or the outer band adjacent the forward end.

The stator vane of any preceding claim, wherein the at least one of the inner band or the outer band extends along the axial centerline from a forward end to an aft end, the seal assembly sealingly engaging the at least one of the inner band or the outer band adjacent the aft end.

The stator vane of any preceding claim, wherein the pin comprises a pin shaft and the second wall comprises a passage surface defining the passage, the pin shaft extending through the passage such that the pin shaft is spaced apart from the passage surface.

The stator vane of any preceding claim, wherein the second wall includes a first surface partially defining the channel, and a second surface spaced from the first surface, the passageway including a notch extending from the first surface to the second surface.

The stator vane of any preceding claim wherein the inner band and the outer band are formed of a composite material and the leaf seal, the seal retainer, the spring, and the pin are formed of a metallic material.

Drawings

A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

FIG. 1 is a schematic cross-sectional view of an embodiment of a gas turbine engine;

FIG. 2 is a partial cross-sectional side view of an embodiment of a turbine section of a gas turbine engine, particularly illustrating a pair of seal assemblies in sealing engagement with forward ends of stator vanes of the engine;

FIG. 3 is a partial cross-sectional side view of another embodiment of a turbine section of a gas turbine engine, particularly illustrating a seal assembly in sealing engagement with an aft end of a stator vane of the engine;

FIG. 4 is a perspective view of an embodiment of a seal assembly for a gas turbine engine, particularly illustrating the seal assembly including a leaf seal, a seal retainer, a pair of pins, and a pair of springs;

FIG. 5 is an enlarged partial perspective view of the seal assembly shown in FIG. 4 with the pin and spring removed for clarity; and

FIG. 6 is a partial cross-sectional view of the seal assembly shown in FIGS. 4 and 5 with the leaf seal, seal retainer and spring removed for clarity.

Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention.

Detailed Description

Reference will now be made in detail to exemplary embodiments of the presently disclosed subject matter, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of illustration and should not be construed to limit the present disclosure. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope or spirit of the disclosure. For instance, features illustrated or described as part of one embodiment, can be used with another embodiment to yield a still further embodiment. It is therefore intended that the present disclosure cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

As used herein, the terms "first," "second," and "third" may be used interchangeably to distinguish one component from another, and are not intended to denote the position or importance of an individual component.

Further, the terms "upstream" and "downstream" refer to relative directions with respect to fluid flow in the fluid pathway. For example, "upstream" refers to the direction from which the fluid flows, and "downstream" refers to the direction to which the fluid flows.

Further, unless otherwise noted, the terms "low," "high," or their corresponding comparison levels (e.g., lower, higher, where applicable) all refer to relative speeds within the engine. For example, the "low pressure turbine" operates at a substantially lower pressure than the "high pressure turbine". Alternatively, the above terms may be understood at their highest level unless otherwise specified. For example, "low pressure turbine" may refer to the lowest maximum pressure turbine within the turbine section, while "high pressure turbine" may refer to the highest maximum pressure turbine within the turbine section.

In general, the present subject matter relates to seal assemblies for gas turbine engines. As will be described below, one or more of the disclosed seal assemblies may be configured to seal a gap(s) defined between adjacent stationary components of a gas turbine engine. For example, in one embodiment, the seal assembly(s) provide a seal between an aft end of a combustor liner (liner) of the engine and a forward end of an adjacent stator vane of the engine. Thus, in such embodiments, the seal assembly(s) reduce or prevent combustion gases from exiting the hot gas path of the engine through the gap(s) between the combustor liner and the stator vanes.

Each seal assembly includes a leaf seal, a seal retainer, one or more springs, and one or more pins. More specifically, the leaf seal is positioned partially within a channel defined between a first wall and a second wall of a stationary gas turbine engine component (e.g., an inner or outer band of a stator vane) such that the leaf seal is in contact with the first wall. Further, a seal retainer is coupled to the second wall. In one embodiment, the seal retainer may include a hook wrapped around the second wall, thereby securing the seal retainer to the second wall. Further, spring(s) are positioned within the channel and compressed between the seal retainer and the leaf seal such that the leaf seal is in sealing engagement with the first wall. Further, the pin(s) extend through the passageway(s) defined by the second wall to couple the seal retainer and the leaf seal. For example, in one embodiment, the passageway(s) may correspond to notch(s) in the second wall.

The passageway(s) defined by the second wall allows for unconstrained thermal growth of the pin(s) during operation (e.g., thermal cycling) of the gas turbine engine. In some cases, the securing member is formed of a composite material, while the components of the seal assembly (e.g., the leaf seal, the seal retainer, the spring(s), and the pin (s)) are formed of a metallic material. In such cases, the securing member and the seal assembly thermally expand and contract at different rates. In this regard, the passageway(s) defined by the second wall are larger than the pin(s) extending therethrough. In this regard, the pin(s) are spaced from the surface(s) of the second wall defining the passageway(s), thereby allowing the pin(s) to thermally expand and contract without being constrained by the securing member. Accordingly, the disclosed seal assembly allows for coupling a metal leaf seal to a composite gas turbine engine component.

Referring now to the drawings, FIG. 1 is a schematic cross-sectional view of an embodiment of a gas turbine engine 10. In the illustrated embodiment, the engine 10 is configured as a high bypass turbofan engine. However, in alternative embodiments, engine 10 may be configured as a paddle fan engine, a turbojet engine, a turboprop engine, a turboshaft gas turbine engine, or any other suitable type of gas turbine engine.

As shown in fig. 1, the engine 10 defines a longitudinal direction L, a radial direction R, and a circumferential direction C. Generally, the longitudinal direction L extends parallel to the axial centerline 12 of the engine 10, the radial direction R extends orthogonally outward from the axial centerline 12, and the circumferential direction C extends generally concentrically about the axial centerline 12.

In general, the engine 10 includes a fan 14, a Low Pressure (LP) spool 16, and a High Pressure (HP) spool 18 at least partially surrounded by an annular nacelle 20. Such a configuration is known as a closed rotor engine. More specifically, fan 14 may include a fan rotor 22 and a plurality of fan blades 24 (one shown) coupled to fan rotor 22. In this regard, fan blades 24 are spaced apart from each other along circumferential direction C and extend outwardly from fan rotor 22 along radial direction R. Further, the LP spool 16 and the HP spool 18 are positioned downstream from the fan 14 along the axial centerline 12 (i.e., in the longitudinal direction L). As shown, the LP spool 16 is rotatably coupled to the fan rotor 22, thereby allowing the LP spool 16 to rotate the fan 14. Further, a plurality of outlet guide vanes or struts 26 spaced from each other in the circumferential direction C extend in the radial direction R between a casing 28 surrounding the LP and HP spools 16, 18 and the nacelle 20. In this regard, the struts 26 support the nacelle 20 relative to the housing 28 such that the housing 28 and the nacelle 20 define a bypass airflow passage 30 positioned therebetween. However, in alternative embodiments, the engine 10 may have an open rotor configuration in which the nacelle 20 is not present.

The casing 28 generally surrounds or encloses, in series flow order, a compressor section 32, a combustion section 34, a turbine section 36, and an exhaust section 38. For example, in some embodiments, the compressor section 32 may include a Low Pressure (LP) compressor 40 of the LP spool 16, and a High Pressure (HP) compressor 42 of the HP spool 18 positioned downstream along the axial centerline 12 from the LP compressor 40. Each compressor 40,42 may, in turn, include one or more rows of stator vanes 44 interdigitated with one or more rows of compressor rotor blades 46. Moreover, in some embodiments, the turbine section 36 includes a High Pressure (HP) turbine 48 of the HP spool 18, and a Low Pressure (LP) turbine 50 of the LP spool 16 positioned downstream along the axial centerline 12 from the HP turbine 48. Each

turbine

48,50 may, in turn, include one or more rows of stator vanes 52 interdigitated with one or more rows of turbine rotor blades 54.

Further, the LP spool 16 includes a Low Pressure (LP) shaft 56, and the HP spool 18 includes a High Pressure (HP) shaft 58 concentrically positioned about the LP shaft 56. In such embodiments, the HP shaft 58 rotatably couples the rotor blades 54 of the HP turbine 48 and the rotor blades 46 of the HP compressor 42 such that rotation of the HP turbine rotor blades 54 rotatably drives the HP compressor rotor blades 46. As shown, the LP shaft 56 is directly coupled to the rotor blades 54 of the LP turbine 50 and the rotor blades 46 of the LP compressor 40. Further, LP shaft 56 is coupled to fan 14 via a gearbox 60. In this regard, rotation of the LP turbine rotor blades 54 rotatably drives the LP compressor rotor blades 46 and the fan blades 24.

In several embodiments, engine 10 may generate thrust to propel an aircraft. More specifically, during operation, air (indicated by arrow 62) enters an inlet portion 64 of engine 10. The fan 14 supplies a first portion of the air 62 (indicated by arrow 66) to the bypass airflow passage 30 and a second portion of the air 62 (indicated by arrow 68) to the compressor section 32. A second portion 68 of the air 62 flows first through the LP compressor 40, where the rotor blades 46 therein progressively compress the second portion 68 of the air 62 in the LP compressor 40. Next, the second portion 68 of the air 62 flows through the HP compressor 42, where the rotor blades 46 therein continue to progressively compress the second portion 68 of the air 62 within the HP compressor 42. The compressed second portion 68 of the air 62 is then delivered to the combustion section 34. In the combustion section 34, a second portion 68 of the air 62 is mixed with fuel and combusted to generate high temperature and high pressure combustion gases 70. Thereafter, the combustion gases 70 flow through the HP turbine 48, wherein the HP turbine rotor blades 54 extract a first portion of the kinetic and/or thermal energy from the combustion gases 70. This energy extraction rotates the HP shaft 58, thereby driving the HP compressor 42. The combustion gases 70 then flow through the LP turbine 50, wherein the LP turbine rotor blades 54 extract a second portion of the kinetic and/or thermal energy from the combustion gases 70. This energy extraction rotates LP shaft 56, thereby driving LP compressor 40 and fan 14 via gearbox 60. In other embodiments, the LP shaft 56 may directly drive the fan 14 (i.e., the engine 10 does not include the gearbox 60). The combustion gases 70 then exit the engine 10 through the exhaust section 38.

FIG. 2 is a partial cross-sectional side view of an embodiment of a HP turbine 48 of gas turbine engine 10. More specifically, FIG. 2 illustrates a first row of stator vanes 52 and a first row of rotor blades 54 of the HP turbine 48. As shown, the first row of stator vanes 52 is positioned downstream of the combustor casing 72 of the combustion section 34 (i.e., with respect to the flow of the combustion gases 70). Each stator vane 52 includes an inner band 74 and an outer band 76, the outer band 76 being positioned outward of the inner band 74 in the radial direction R and spaced apart from the inner band 74. The inner and

outer bands

74, 76 are in turn positioned adjacent a downstream end 78 of the combustor casing 72. Further, each stator vane 52 includes an airfoil 80 that extends in the radial direction R between the inner band 74 and the outer band 76. A first row of rotor blades 54 is positioned adjacent to the first row of stator vanes 52 and downstream from the first row of stator vanes 52. Further, shroud 82 is positioned outboard of first row of rotor blades 54 in radial direction R. Further, shroud 82 surrounds or otherwise surrounds first row of rotor blades 54 such that shroud 82 is adjacent outer band 76.

Further, the HP turbine 48 includes one or more seals or seal assemblies. Generally, the seal (s)/seal assembly(s) reduce or prevent the combustion gases 70 from exiting the hot gas path 84 flowing through the combustion section 34 and the turbine section 36. As shown, in several embodiments, one or more seal assemblies 100 seal the gap 86 between the combustor casing 72 and the first row of stator vanes 52. For example, in the illustrated embodiment, the seal assembly 100 sealingly engages the downstream end portion 78 of the combustor casing 72 and the forward end portion 88 of the inner band 74 of each stator vane 52. Further, in the illustrated embodiment, another seal assembly 100 sealingly engages the downstream end portion 78 of the combustor casing 72 and the forward end portion 90 of the outer band 76 of each stator vane 52. The construction of the seal assembly 100 will be described in detail below. Further, the W-seal 92 may sealingly engage the aft end 94 of the outer band 76 of each stator vane 52 and the shroud 82.

FIG. 3 is a partial cross-sectional side view of another embodiment of a HP turbine 48 of the gas turbine engine 10. As shown, the HP turbine 48 shown in fig. 3 is configured similarly to the HP turbine 48 shown in fig. 2. For example, like the HP turbine 48 shown in FIG. 2, the HP turbine 48 of FIG. 3 includes a seal assembly 100, the seal assembly 100 sealing the gap 86 between the combustor casing 72 and the first row of stator vanes 52. However, unlike the HP turbine 48 shown in fig. 2, the HP turbine 48 of fig. 3 includes a seal assembly 100, the seal assembly 100 sealingly engaging the aft end 94 of the outer band 76 of each stator vane 52 and the shroud 82.

The sealing configuration shown in fig. 2 and 3 is provided as an exemplary embodiment. In this regard, the engine 10 may include seal(s) or any other suitable type or configuration of seal assembly(s) in place of or in addition to the seal assembly 100 and the W-seal 92 shown in fig. 2 and 3. Further, although not shown in fig. 2 and 3, in other embodiments, the seal assembly 100 may sealingly engage the aft end 96 of the inner band 74 of each stator vane 52.

The configuration of the gas turbine engine 10 described above and shown in FIGS. 1-3 is merely provided to place the present subject matter in an exemplary field of use. Thus, the present subject matter may be readily adapted to any manner of gas turbine engine configuration, including other types of aeronautical-based gas turbine engines, marine-based gas turbine engines, and/or land/industrial-based gas turbine engines. (to this)

FIG. 4 is a perspective view of an embodiment of a seal assembly 100 for a gas turbine engine. In general, the seal assembly 100 will be described in the context of the stator vanes 52 of the gas turbine engine 10 shown in fig. 1-3. However, the disclosed seal assembly 100 may be used with any other suitable component(s) of the gas turbine engine 10, or with any suitable component(s) of another gas turbine engine.

As shown in FIG. 4, in several embodiments, the seal assembly 100 is in sealing engagement with the forward end 90 of the outer band 76 of one of the stator vanes 52. In such embodiments, the stator vane 52 includes a first wall 102, the first wall 102 extending outwardly from the forward end 90 of the outer band 76 in the radial direction R. Further, in such embodiments, the stator vane 52 includes a second wall 104, the second wall 104 extending outwardly from the forward end 90 of the outer band 76 in the radial direction R. The second wall 104 is spaced apart from the first wall 102 and is positioned aft (i.e., downstream with respect to the flow of the combustion gases 70) of the first wall 102. In this regard, the first wall 102 and the second wall 104 define a channel 106 positioned therebetween along the longitudinal direction L. As will be described below, the leaf seal 108 of the seal assembly 100 is partially positioned within the channel 106. In some embodiments, in addition to or in lieu of first and

second walls

102, 104 extending outwardly from outer band 76, first and second walls may extend inwardly from forward end 88 of inner band 74 in radial direction R. Further, in further embodiments, the first and second walls may extend inwardly/outwardly from the rear end 96 of the inner band 74 and/or the rear end 94 of the outer band 76 in the radial direction R in addition to or in lieu of the first and second walls extending inwardly/outwardly from the front ends 88,90 of the inner and/or

outer bands

74, 76.

In several embodiments, the seal assembly 100 includes a leaf seal 108, a seal retainer 110, one or more springs 112, and one or more pins 114. More specifically, as shown, the leaf seal 108 is partially positioned within the channel 106, the channel 106 being defined between the first wall 102 and the second wall 104. Further, a seal retainer 110 is coupled to the second wall 104. For example, in some embodiments, the seal holder 110 slides over the second wall 104 in a sleeve-like manner. Further, a pair of springs 112 are compressed between the seal retainer 110 and the leaf seal 108 such that the leaf seal 108 is in sealing engagement with the first wall 102 and an adjacent component of the engine 10, such as the downstream end 78 of the combustor case 72 (fig. 2). Further, as will be described below, a pair of pins 114 extend through a pair of passages 116 (one shown) defined by the second wall 104 to couple the seal holder 110 and the leaf seal 108. The pins 114 are in turn spaced from each other in the circumferential direction C. However, in alternative embodiments, the seal assembly 100 may include any other suitable number of springs 112, pins 114, and passages 116.

Fig. 5 is an enlarged partial perspective view of the seal assembly 100 with the spring 112 and pin 114 removed for clarity. As shown, the second wall 104 includes various surfaces. More specifically, the second wall 104 includes a first surface 118 that defines a portion of the channel 106, and a second surface 120 that is spaced apart from the first surface 118 along the longitudinal direction L. Further, the first surface 118 and the second surface 120 extend in the radial direction R and the circumferential direction C. In addition, the second wall 104 includes a third surface 122 extending between the first surface 118 and the second surface 120. In this regard, the third surface 122 extends in the longitudinal direction L and the radial direction R. Further, the second wall 104 includes a fourth surface 124 extending between the first surface 118 and the second surface 120, wherein the fourth surface 124 is orthogonal to the third surface 122. In this regard, the fourth surface 124 extends in the longitudinal direction L and the circumferential direction C.

As mentioned above, in some embodiments, the packing retainer 110 is coupled to the second wall 104 by sliding the packing retainer 110 over the second wall 104 in a sleeve-like manner. More specifically, the packing retainer 110 includes a packing retainer body 126, and a pair of packing retainer hooks 128 (one shown in FIG. 5) coupled to the body 126. As shown, when the packing retainer 110 is coupled to the second wall 104, the packing retainer body 126 is in contact with the second surface 120 of the second wall 104. Thus, the seal holder body 126 is spaced from the channel 106 by the second wall 104 in the longitudinal direction L. Additionally, the seal retainer hooks 128 extend outwardly from the seal retainer body 126 and around the fourth surface 124 of the second wall 104 such that a portion of each hook 128 is in contact with the first surface 118 of the second wall 104. However, in alternative embodiments, the packing retainer 110 may be coupled to the second wall 104 in any other suitable manner.

Further, the packing retainer 110 may include support arms 130 (shown in FIG. 2). Specifically, when the seal assembly 100 is in sealing engagement with the outer band 76 of the stator vane 52, the seal retainer 110 may include support arms 130. In such a case, the support arm 130 prevents the seal holder 110 from rotating relative to the second wall 104. In this regard, the support arm 130 may extend outwardly from the seal holder body 126 in the longitudinal direction L. For example, as shown in FIG. 2, when seal assembly 100 is in sealing engagement with forward end 90 of outer band 76, support arm 130 may extend downstream (i.e., with respect to the flow of combustion gases 70) from seal holder body 126 in longitudinal direction L. Conversely, when seal assembly 100 is in sealing engagement with aft end 94 of outer band 76, support arm 130 may extend upstream (i.e., with respect to the flow of combustion gases 70) from seal holder body 126 in longitudinal direction L. However, in some embodiments, the seal retainer 110 may not include support arms 130, such as when the seal assembly 100 is in sealing engagement with the inner band 74 of the stator vane 52.

Referring again to fig. 5, as mentioned above, in several embodiments, the second wall 104 defines a pair of passages 116, with the pins 114 (fig. 4) extending through the pair of passages 116. As shown in fig. 5, the passage 116 extends through the second wall 104 from the first surface 118 to the second surface 120. In this regard, the seal holder body 126 defines a pair of apertures 132 (one shown). Each aperture 132 is in turn aligned with one of the passages 116 in the radial direction R and the circumferential direction C to allow the pin 114 to extend through the seal holder 110 and the passage 116.

FIG. 6 is a partial cross-sectional view of the seal assembly 100 with the leaf seal 108, seal retainer 110, and spring 112 removed for clarity. As shown, in several embodiments, the passage 116 is configured as a notch 134. Specifically, in such embodiments, the notch 134 extends in the circumferential direction C from an opening 136 into the second wall 104, the opening 136 being defined by the third surface 122 of the second wall 104. The notch 134 also extends from the first surface 118 of the second wall 104 through the second surface 120 of the second wall 104 along the longitudinal direction L. However, in alternative embodiments, the passages 116 may be configured in any other suitable manner. For example, in an alternative embodiment, the passage 116 may be configured as a through-hole extending between the first surface 118 and the second surface 120 of the second wall 104, wherein the through-hole is spaced apart from the third surface 122 of the second wall 104 in the circumferential direction C.

Further, passage 116 is sized to accommodate unconstrained thermal growth of pin 114 extending therethrough during operation of engine 10. In several embodiments, the stator vane 52 is formed from a composite material (e.g., a Ceramic Matrix Composite (CMC) material), while the components of the seal assembly 100 (e.g., the leaf seal 108, the seal retainer 110, the spring(s) 112, and the pin(s) 114) are formed from a metallic material. In such embodiments, the stator vanes 52 and the seal assembly 100 thermally expand and contract at different rates during operation (e.g., thermal cycling) of the engine 10. In this regard, the passage 116 defined by the second wall 104 is larger than the pin 114 extending therethrough. Specifically, the diameter (indicated by arrow 138) of each passage 116 is greater than the diameter (indicated by arrow 140) of the pin shaft 142 of the pin 114 extending through such passage 116. The diameter 138 of the passage 116 may in turn be the smallest dimension of the passage 116 in a plane defined by the radial direction R and the circumferential direction C. In this regard, each pin 114 is spaced from a passage surface 144 of the second wall 104 defining the corresponding passage 116. For example, in one embodiment, each pin 114 is spaced 360 degrees from the corresponding passage surface 144. Thus, during operation of engine 10, pins 114 may thermally expand and contract without being constrained by second wall 104, thereby allowing metal seal assembly 100 to be coupled to a composite component (e.g., one of stator vanes 52) of gas turbine engine 10.

This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

Further aspects of the invention are provided by the subject matter of the following clauses:

a seal assembly for a gas turbine engine, the seal assembly comprising: a first gas turbine wall; a second gas turbine wall spaced apart from the first gas turbine wall, the first and second gas turbine walls defining a channel therebetween, the second gas turbine wall further defining a passage extending through the second gas turbine wall; a leaf seal positioned partially within the channel; a seal retainer coupled to the second gas turbine wall; a spring compressed between the seal retainer and the leaf seal such that the leaf seal is in sealing engagement with the first gas turbine wall; and a pin extending through the passage defined by the second gas turbine wall to couple the seal retainer and the leaf seal such that the pin is not thermally constrained by the second wall during operation of the gas turbine engine.

The seal assembly of one or more of these clauses wherein the pin comprises a pin shaft having a pin shaft diameter that is less than the diameter of the passageway.

The seal assembly of one or more of these clauses, wherein the second gas turbine wall includes a passage surface defining the passage, the pin extending through the passage such that the pin is spaced apart from the passage surface.

The seal assembly of one or more of these clauses wherein the second gas turbine wall includes a first surface partially defining the passage, a second surface spaced from the first surface, and a third surface extending between the first surface and the second surface, the passage extending from the first surface to the second surface.

The seal assembly of one or more of these clauses wherein the passageway comprises a recess.

The seal assembly of one or more of these clauses, wherein the third surface of the second gas turbine wall defines an opening of the recess.

The seal assembly of one or more of these clauses, wherein the seal retainer comprises a body and a hook coupled to the body, the body being in contact with the second surface, at least a portion of the hook being in contact with the first surface.

The seal assembly of one or more of these clauses, wherein the second gas turbine wall further comprises a fourth surface extending between the first surface and the second surface, the fourth surface being orthogonal to the third surface, the hook extending from the body around the fourth surface to contact the first surface.

The seal assembly of one or more of these clauses wherein the seal retainer comprises a support arm configured to prevent rotation of the seal retainer relative to the second gas turbine wall.

The seal assembly of one or more of these clauses wherein said first gas turbine wall and said second gas turbine wall are formed from a composite material.

The seal assembly of one or more of these clauses wherein said leaf seal, said seal retainer, said spring, and said pin are formed from a metallic material.

A stator vane for a gas turbine engine defining an axial centerline, the stator vane comprising: an inner band; an outer band spaced from the inner band in a radial direction extending orthogonally outward from the axial centerline; an airfoil extending between the inner band and the outer band; a first wall extending outwardly from at least one of the inner band or the outer band in the radial direction; a second wall extending outwardly from the at least one of the inner band or the outer band in the radial direction, the second wall being spaced apart from the first wall along the axial centerline, the first wall and the second wall defining a channel therebetween, the second wall further defining a passageway extending therethrough; and a seal assembly comprising: a leaf seal positioned partially within the channel; a seal retainer coupled to the second wall; a spring compressed between the seal retainer and the leaf seal such that the leaf seal is in sealing engagement with the first wall; and a pin extending through the passage defined by the second wall to couple the seal retainer and the leaf seal such that the pin is not thermally constrained by the second wall during operation of the gas turbine engine.

The stator vane of one or more of these clauses wherein the seal assembly sealingly engages the outer band.

The stator vane of one or more of these clauses wherein the seal retainer comprises a support arm configured to prevent rotation of the seal retainer relative to the second wall.

The stator vane of one or more of these clauses, wherein the seal assembly sealingly engages the inner band.

The stator vane of one or more of these clauses wherein the at least one of the inner band or the outer band extends along the axial centerline from a forward end to an aft end, the seal assembly sealingly engaging the at least one of the inner band or the outer band adjacent the forward end.

The stator vane of one or more of these clauses wherein said at least one of said inner band or said outer band extends along said axial centerline from a forward end to an aft end, said seal assembly sealingly engaging said at least one of said inner band or said outer band adjacent to said aft end.

The stator vane of one or more of these clauses wherein the pin comprises a pin shaft and the second wall comprises a passage surface defining the passage, the pin shaft extending through the passage such that the pin shaft is spaced apart from the passage surface.

The stator vane of one or more of these clauses, wherein the second wall comprises a first surface partially defining the passage, and a second surface spaced from the first surface, the passageway comprising a notch extending from the first surface to the second surface.

The stator vane of one or more of these clauses wherein the inner band and the outer band are formed of a composite material and the leaf seal, the seal retainer, the spring, and the pin are formed of a metallic material.

Claims

1. A seal assembly for a gas turbine engine, the seal assembly comprising:

a first gas turbine wall;

a leaf seal positioned partially within the channel;

a seal retainer coupled to the second gas turbine wall;

2. The seal assembly of claim 1, wherein the pin comprises a pin shaft having a pin shaft diameter that is smaller than a passage diameter of the passage.

3. The seal assembly of claim 2, wherein the second gas turbine wall includes a passage surface defining the passage, the pin extending through the passage such that the pin is spaced apart from the passage surface.

4. The seal assembly of claim 1, wherein the second gas turbine wall includes a first surface partially defining the passage, a second surface spaced from the first surface, and a third surface extending between the first surface and the second surface, the passage extending from the first surface to the second surface.

5. The seal assembly of claim 4, wherein the passage comprises a notch.

6. The seal assembly of claim 5, wherein the third surface of the second gas turbine wall defines an opening of the recess.

7. The seal assembly of claim 6, wherein the notch extends from the opening into the second gas turbine wall in a circumferential direction that extends concentrically about an axial centerline of the gas turbine engine.

8. The seal assembly of claim 4, wherein the seal retainer comprises a body and a hook coupled to the body, the body being in contact with the second surface, at least a portion of the hook being in contact with the first surface.

9. The seal assembly of claim 8, wherein the second gas turbine wall further includes a fourth surface extending between the first and second surfaces, the fourth surface being orthogonal to the third surface, the hook extending from the body around the fourth surface to contact the first surface.

10. The seal assembly of claim 1, wherein the seal retainer comprises support arms configured to prevent rotation of the seal retainer relative to the second gas turbine wall.